Thuja plant named ‘Silvanus 1’

ABSTRACT

‘Silvanus 1’ is a new variety of  Thuja occidentalis  that exhibits medium dense branching and is suitable for use as a solitary garden plant or for use as a field hedge.

Botanical classification: Thuja occidentalis.

Varietal denomination: ‘Silvanus 1’.

CROSS REFERENCE TO RELATED APPLICATION

The present invention claims priority to Hungarian Plant Patent Application No. F04 00057, filed on Sep. 22, 2004.

BACKGROUND OF THE INVENTION

The present invention comprises a new and distinct cultivar of Thuja occidentalis known by the varietal name ‘Silvanus 1’. The new variety was discovered by the breeder as a naturally-occurring branch (sport) mutation of Thuja occidentalis ‘Smaragd’ in West Hungary. ‘Silvanus 1’ was first asexually reproduced by semi-hardwood cuttings in West Hungary. The new variety has been trial and field tested and has been found to retain its distinctive characteristics and remain true to type through successive propagations. Table 1 illustrates characteristics that distinguish ‘Silvanus 1’ from its parent plant, ‘Smaragd’.

TABLE 1 Characteristic ‘Silvanus 1’ ‘Smaragd’ Plant habit Ovoid Conic Plant speed of growth Slow Medium Color of upper leaf side in Light green Green Summer Side branch position Vertical Horizontal Scale leaf width Narrow Medium Scale leaf thickness Thin to medium Medium

DESCRIPTION OF THE DRAWINGS

The accompanying photographic drawings illustrate the new variety, with the color being as nearly true as is possible with color illustrations of this type:

FIG. 1 shows an entire plant of the new variety; and

FIG. 2 shows an entire field of the new variety.

DESCRIPTION OF THE PLANT

The following detailed description sets forth the characteristics of the new cultivar. The data which defines these characteristics were collected by asexual reproductions carried out in West Hungary. The new variety was grown outside without shade in average productivity soil after a Summer season that experienced more rain than average. ‘Silvanus 1’ was four years old when described and was grown free range (without a container). The color readings were taken outdoors under natural light. Color references are primarily to the R.H.S. Colour Chart of The Royal Horticultural Society of London.

GROWTH AND PROPAGATION

-   Plant type and use: Squamifoliate evergreen plant (conifer). It can     be used solitarily in gardens or grouped as a field hedge. -   Growth habit: Ovoid. -   Height: 50 cm. -   Spread: 22 cm. -   Hardiness: Zone 5, between 28.8-23.4° C. -   Propagation protocol: The new variety grafts well and, similar to     ‘Smaragd’, ‘Silvanus 1’ can be propagated by cuttings successfully.     As the plant takes root well, the cutting is the most important     propagation protocol in the nursery. The cuttings are taken     immediately from the semi-hardwood shoots taken off the mother     plants. Please note that only semi-hardwood cuttings can root, as     soft cuttings root off in the radication medium and cannot take     root. Also, fewer cuttings can be taken from ‘Silvanus 1’ because it     is slower growing than ‘Smaragd’. The cuttings are taken from the     end of August until April, by the beginning of prolification. The     radication medium used is 0.2 mm granulation-sterile buddled gravel.     For a better rooting, each cutting is dipped (about 1 mm deep) into     0.6% IBA (indole butric acid). The cuttings are grown in a temperate     glasshouse. The temperature of the rooting medium should be between     19 and 20° C. and the temperature of the air must always be cooler.     Low temperatures (up to −5° C.) also provide a stronger root system.     Automatic overhead irrigation is supplied 2-3 times a day, depending     on the weather. The cuttings take root in 9-12 weeks. The growing     can then proceed in 9×9 plastic pots or in open ground. -   Time to initiate roots: Approximately 42 to 56 days, with the     temperature of radication medium being 19-20° C. and the maximum     temperature of the air being 16-17° C. -   Time to develop roots: Approximately 21 to 28 days, with the     temperature of radication medium being 19-20° C. and the maximum     temperature of the air being 16-17° C. -   Rooting habit: Adventitious and fibrous root system. -   Trunk:     -   -   Surface texture.—Reticulate and scaly.         -   Color.—Greyed-Orange group 177A.         -   Diameter.—28 mm at 50 mm in height. -   Disease/pest resistance: No resistance or susceptibility has been     observed to date.

STEM DESCRIPTION

-   Shape:     -   -   Twigs.—Upright.         -   Mature branches.—Upright. -   Color:     -   -   Twigs.—Greyed-Orange Group 177B.         -   Young branches.—Greyed-Orange Group 164C.         -   Mature branches.—Greyed-Orange Group 177B. -   Diameter:     -   -   Twigs.—8 mm.         -   Main branches.—5 mm.         -   Secondary branches.—2.5 mm. -   Length (measured on a six-year old plant):     -   -   Twigs.—11.3 cm.         -   Main branches.—31.5 cm.         -   Secondary branches.—10.2 cm. -   Surface description:     -   -   Twigs.—Fibrous, vertically striated.         -   Main branches.—Medium striation.         -   Secondary branches.—Minor striation. -   Branching description: The branching is medium dense and it is     arranged in vertical levels. The branching is similar to Thuja     orientalis ‘Aurea Nana’ (syn: Thuja orientalis ‘Berkmannii’). -   Branch aspect description: Similar to Thuja occidentalis ‘Smaragd’,     but its structure is thinner and finer.

FOLIAGE DESCRIPTION

-   Leaf:     -   -   Color.—Green Group 143C.         -   Arrangement.—Opposite.         -   Fragrance.—Resin-smelling (if rubbed).         -   Shape.—Flattened squama.         -   Length.—2.5 mm.         -   Width.—Narrow, approximately 1.5-2 mm.         -   Division.—Overlap as a squama.         -   Base.—Oval.         -   Apex.—Pointed; sharp.         -   Margin.—Entire.         -   Surface texture.—Upper surface: Glandular points rise with             an X motif because of overlapping scale leafs. Lower             surface: X motif because of overlapping scale leafs.         -   Resin glands.—Location: At glandular point rises. Shape:             Square. Color: Green. -   Cone description: Not available as cones are not yet present. -   Seed description: Not available as seeds are not yet present. 

1. A new and distinct variety of Thuja occidentalis plant named ‘Silvanus 1’ as is herein described and illustrated. 